CROSTATA WITH CHOCOLATE, HAZELNUTS, AND ORANGE

Steps:

• Arrange a rack in the middle of the oven with a baking stone on it, if you have one. Preheat the oven to 350°.
• Roll and press the dough to form the tart shell, as detailed in the box on page 403. Put the shell in the refrigerator to chill.
• Put the 5 ounces of chocolate chunks in a bowl, and set over a pot of very hot water (barely simmering). Stir as the chocolate begins to melt, enabling it to become molten at the lowest temperature. When completely smooth, pour the chocolate into the tart shell, and spread it to cover the dough bottom completely.
• Put the hazelnuts in the food processor, and pulse to chop them into small bits-don't turn them into a powder or paste. Empty the nuts into a bowl, and wipe out the food processor (you don't have to wash it).
• To prepare the orange zest for the filling, rinse and dry the orange, and remove only the outer, colored zest in strips, about 2 inches long, with a vegetable peeler. Stack up a few strips at a time and slice them lengthwise into very thin slivers with a sharp paring knife. Then cut the slivers crosswise into tiny bits, like glitter or small confetti; you should have about 2 tablespoons.
• Now you'll blend the main filling in the processor, adding the ingredients separately; frequently scrape down the sides of the bowl to make sure everything is processed evenly. First blend the sugar and butter, processing about 30 seconds, until smooth. With the machine running, drop in the eggs and process for a minute or more, until smooth and slightly thickened (be sure to scrape the sides). Drop in the flour and blend until smooth; scrape the bowl.
• With the machine off, drop in the chopped orange peel, chocolate, and hazelnuts, and pulse for only a second or two to incorporate. Finally, whiz in the orange liqueur for just a second. Take the processor bowl off the base, and scrape the filling from the sides and blade. Stir one last time, and pour it into the tart shell. Smooth the surface with a spatula to form an even layer.
• Set the tart mold on the hot baking stone, if you have one, or on the middle oven rack. Bake for 25 minutes or so, and rotate the mold for even baking. As the filling sets, it will start to crack around the edges (when it starts to crack in the center, it is done). Bake 35 to 40 minutes total, until the filling is puffed, and firm in the center, and a cake tester comes out clean. The tart crust should be nicely browned as well.
• Set the baked tart on a wire rack to cool. If using a tart ring with a removable bottom, remove the ring; slide the tart off the round mold bottom onto a platter if you want.
• Serve slightly warm or at room temperature, with whipped cream, if desired.
• Into the bowl of a food processor fitted with the metal blade, drop the flour, baking powder, salt, and sugar. Process for a few seconds, to mix the dry ingredients.
• Cut the butter into 1/2-inch pieces, drop them onto the flour, and pulse the machine ten or twelve times, in short bursts, 20 to 30 seconds in all. The mixture should be crumbly, with only a few larger bits of butter visible.
• Drop the egg yolks into the processor and pulse in bursts, just until the dough starts to clump together in bigger crumbs-it won't form a single mass. Scrape out the wet crumbs, press them together, and knead just for a few seconds, to form a smooth, tight dough. Flatten it into a disk, wrap well in plastic wrap, and refrigerate for 3 hours or up to a day before using. Freeze the dough for longer keeping.
• Let the chilled dough sit at room temperature for 10 minutes or so before rolling. Thaw frozen dough completely, preferably in the refrigerator, before using.
• For either of the tart recipes here-or anytime you use this dough-follow these basic procedures to line a tart mold, turning the dough into a thin shell. I use a standard 9-inch metal tart mold with a fluted ring and removable round bottom, but this dough can line any 9-inch pan.
• Let the chilled dough soften briefly, but don't let it get too warm. Put the disk of dough in between two pieces of wax paper or parchment (about 1-foot squares) and roll it out to an 11-inch circle: roll from the center, in all directions, trying to stretch the dough evenly. With 12-inch-wide paper, roll to a circle that comes right to the edge.
• Chill the dough circle in the refrigerator after rolling, inside the paper-this always helps. Peel the top paper off the dough, and center it over the tart mold. Peel off the other paper sheet; if the paper doesn't come off easily, chill again, then remove. Press the dough gently down into the mold so it covers the bottom and comes up the sides.
• If the dough is cooperative, it may line the shell perfectly, and all you will have to do is even out the sides. But if it breaks into pieces or is uneven, you can press it into shape with your fingers. Here are some tips that will help you:
• Keep the dough cold: put it in the refrigerator whenever you have trouble.
• Moisten your fingers lightly to press and push the dough without its sticking to you (but don't drip water in the shell). Move dough from thick spots to thin spots, until the bottom is evenly thick all over.
• To shape the sides, press the dough against the fluted rim with your index finger to form an evenly thick wall all the way around. Remove any dough that's higher than the rim by flicking it against the sharp rim; put these bits back in the mold.
• When the shell is finished, chill it in the refrigerator before filling.